Linear magnetoresistance in topological insulators: Quantum phase coherence effects at high temperatures

TL;DR

This study reveals that topological insulators exhibit a high-field linear magnetoresistance at temperatures up to 150K, driven by quantum phase coherence effects that persist at high temperatures.

Contribution

It demonstrates the presence of quantum phase coherence effects causing linear magnetoresistance in topological insulators at high temperatures, extending understanding beyond low-temperature regimes.

Findings

Linear magnetoresistance in Bi2Te2Se persists up to 150K.

High-field MR slope is nearly temperature-independent.

Quantum phase coherence influences MR at high temperatures.

Abstract

In addition to the weak antilocalization cusp observed in the magnetoresistance (MR) of topological insulators at low temperatures and low magnetic fields, we find that the high-field MR in Bi2Te2Se is linear in field. At fields up to B=14T the slope of this linear-like MR is nearly independent of temperature over the range T=7 to 150K. We find that the linear MR arises from the competition between a logarithmic phase coherence component and a quadratic component. The quantum phase coherence dominates up to high temperatures, where the coherence length remains longer than the mean free path of electrons.